A. Field of the Invention
This invention relates generally to methods and apparatus for providing search results in response to an ambiguous search query provided by a user.
B. Description of the Related Art
Most search engines operate under the assumption that the end user is entering search queries using something like a conventional keyboard, where the input of alphanumeric strings is not difficult. As small devices become more common, however, this assumption is not always valid. For example, users may query search engines using a wireless telephone that supports the WAP (Wireless Application Protocol) standard. Devices such as wireless telephones typically have a data input interface wherein a particular action by the user (e.g., pressing a key) may correspond to more than one alphanumeric character. A detailed description of WAP architecture is available at http://www1.wapforum.org/tech/documents/SPEC-WAPArch-19980439.pdf (xe2x80x9cWAP 100 Wireless Application Protocol Architecture Specificationxe2x80x9d).
In the usual case, the WAP user navigates to the search query page, and is presented with a form into which they input their search query. With conventional methods, the user may be required to press multiple keys to select a particular letter. On a standard telephone keypad, for example, the user would select the letter xe2x80x9cbxe2x80x9d by pressing the xe2x80x9c2xe2x80x9d key twice, or would select the letter xe2x80x9csxe2x80x9d by pressing the xe2x80x9c7xe2x80x9d key four time. Accordingly, to enter a query for xe2x80x9cben smithxe2x80x9d, the user would ordinarily need to enter the following string of keypresses: 223366077776444844, which map to letters as follows:
22-xe2x86x92b
33-xe2x86x92e
66-xe2x86x92n
0-xe2x86x92space
7777-xe2x86x92s
6-xe2x86x92m
444-xe2x86x92i
8-xe2x86x92t
44-xe2x86x92h
After the user has entered their search request, the search engine receives the word or words from the user, and proceeds in much the same manner as if it had received the request from a desktop browser wherein the user employed a conventional keyboard.
As can be seen from the foregoing example, this form of data entry is inefficient in that it requires eighteen keystrokes to enter the nine alphanumeric characters (including the space) corresponding to xe2x80x9cben smithxe2x80x9d. Others have attempted to overcome the limitations imposed by reduced data entry devices, but each of the existing approaches has shortcomings. There remains, therefore, a need for methods and apparatus for providing relevant search results in response to an ambiguous search query.
Methods and apparatus consistent with the present invention, as embodied and broadly described herein, provide relevant search results in response to an ambiguous search query. Consistent with the invention, a method of providing search results to a user in response to an ambiguous search query includes generating a first index that associates (1) a first set of information of a first type with (2) documents that correspond to the first set of information. The first set of information is translated into a second set of information of a second type, based on mapping information. A second index is generated that associates, based on the mapping information, (1) the second set of information with (2) the documents. A search query of the second type is received, and search results are generated by comparing the search query to the second index. The user is then presented with these search results.